Magnus Karlsson e8d38fcd0a xsk: Do not sleep in poll() when need_wakeup set ... commit bd0687c18e upstream. Do not sleep in poll() when the need_wakeup flag is set. When this flag is set, the application needs to explicitly wake up the driver with a syscall (poll, recvmsg, sendmsg, etc.) to guarantee that Rx and/or Tx processing will be processed promptly. But the current code in poll(), sleeps first then wakes up the driver. This means that no driver processing will occur (baring any interrupts) until the timeout has expired. Fix this by checking the need_wakeup flag first and if set, wake the driver and return to the application. Only if need_wakeup is not set should the process sleep if there is a timeout set in the poll() call. Fixes: 77cd0d7b3f ("xsk: add support for need_wakeup flag in AF_XDP rings") Reported-by: Keith Wiles <keith.wiles@intel.com> Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/bpf/20211214102607.7677-1-magnus.karlsson@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-12-22 09:32:50 +01:00
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Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	xsk: Introduce AF_XDP buffer allocation API	2020-05-21 17:31:26 -07:00
xdp_umem.c	xsk: Use kvcalloc to support large umems	2021-05-25 13:11:50 +02:00
xdp_umem.h	xsk: Fix umem cleanup bug at socket destruct	2020-11-20 15:52:39 +01:00
xsk.c	xsk: Do not sleep in poll() when need_wakeup set	2021-12-22 09:32:50 +01:00
xsk.h	xdp: Add proper __rcu annotations to redirect map entries	2021-06-24 19:41:15 +02:00
xsk_buff_pool.c	xsk: Fold xp_assign_dev and __xp_assign_dev	2021-01-25 23:56:33 +01:00
xsk_diag.c	xsk: Fix possible segfault in xsk umem diagnostics	2020-09-02 16:49:40 +02:00
xsk_queue.c	xsk: Remove MEM_TYPE_ZERO_COPY and corresponding code	2020-05-21 17:31:27 -07:00
xsk_queue.h	xsk: Fix broken Tx ring validation	2021-06-18 16:59:20 +02:00
xskmap.c	xdp: Add proper __rcu annotations to redirect map entries	2021-06-24 19:41:15 +02:00